Circular piston internal combustion engine

ABSTRACT

A circular piston internal combustion machine with trough-shaped depressions in the circumferential direction of the piston, in which fuel flow deflecting means are provided in said troughshaped depressions for deflecting the fuel flow in the axial direction of the piston which is rotatable relative to the housing.

United States Patent 1151 3,692,001 Hejj 1 51 Sept. 19, 1972 [541CIRCULAR PISTON INTERNAL COMBUSTION ENGINE [56] References Cited [72]Inventor: Erwin Hejj, Essen, Germany UNITED STATES PATENTS 1 Assignee:pp Gesellschafl mit 3,213,836 10/1965 Keylwert et al ..123/s.11beschrankter g, en, Ger- 3,244,154 4/1966 Lohner ..l23/8.ll ny 3,283,75011/1966 Lohner ..l23/8.11 3,297,005 1/1967 Lamm ..l23/8.09 [22] 19713,319,610 5/1967 l-lejj etal. ..123/s.11 [21] App1.No.: 11,552

Primary Examiner-C. J. Husar Related U.S. Appllcatlon Data Ammey wa|terBecker [62] Division of Ser. No. 812,524, March 4, 1969,

Pat. No. 3,610,209. [571 ABSTRACT A circular piston internal combustionmachine with [30] Foreign Application Priority Data trough-shapeddepressions in the circumferential March 6, 1968 Germany ..P 16 01 821.6direct whid fuel defleiting means are provlded 1n said trough-shapeddepresslons for deflecting the fuel flow in the axial direction of the[52] U.S. Cl ..l23/8.09,418/6l 51 1111. C1 .1 ..F02b 55/14 whlch ramblelame the Musmg' [58] Field of Search ..123/8.09, 8.11; 418/61 11 Claims,7 Drawing Figures PATENTEUSEP I973 3.692.001

sum 2 0r 2 Inventor:

CIRCULAR PISTON INTERNAL COMBUSTION ENGINE This is a division of myco-pending application Ser. No. 812,524 filed Mar. 4, 1969 and now US.Pat. No. 3,610,209 belonging to the assignee of the present invention.

The present invention relates to a circular piston internal combustionmachine with a stationary housing which comprises a housing mantle, theinner surface of which in a section transverse to the axis of rotationof the piston relative to the housing has the shape of a multi-arcepitrochoid and also comprises side portions which together with thehousing mantle define an inner chamber. Extending through this innerchamber perpendicularly to the side portions thereof extends aneccentric shaft, the eccentric of which has rotatably journalled thereona polygonal piston the flanks of which are provided with fuel chamberforming depressions extending in the circumferential direction of thepiston.

With heretofore known circular piston internal combustion machines, thepreparation of the fuel air mixture encounters considerabledifficulties. The fuel gas flow is driven by the circulating pistonagainst the outer wall of the working chamber without a sufficientturbulence of the fuel air mixture being obtained. The limitedcompression ratio and the longitudinal extending shape of the workingchambers will not permit the provision of sufficiently large fuelchamber depressions similar to those customary with reciprocatingpistons.

Various suggestions have been made to aid the development of turbulence.Thus, according to German Pat. No. 1,233,651, inserts have been placedin the suction passage, and according to the German Pat. No. 1,238,712and the German Gebrauchsmuster 1,963,642 it has been suggested to blowin air or an air fuel mixture during the suction and compression stroke.A particular motion control disclosed in the British Pat. No. 967,983 isintended to make possible the provision of deeper fuel chamberdepressions. U.S. Pat. No. 3, l 96,852 suggests a fuel injection againstthe piston.

It is an object of the present invention to provide a circular pistoninternal combustion machine in which the preparation of the mixture ofmixture compressing and air compressing circular piston internal comThese and other objects and advantages of the inven- 1 tion will appearmore clearly from the following specification in connection with theaccompanying drawings, in which:

FIG. 1 is a top view of a piston flank with a deflecting body in thefuel chamber depression.

FIG. 2 shows a longitudinal section through the piston flank of FIG. 1.

FIG. 3 illustrates a modified piston flank which differs from that ofFIG. 1 primarily in that it is provided with two deflecting bodies inthe fuel chamber depression.

FIG. 4 is a top view of a piston flank with a deflecting body having adeclining surface in the fuel chamber depression.

FIG. 5 shows a longitudinal section through the piston flank of FIG. 4.

FIG. 6 is a top view of a modified piston flank in which the fuelchamber depression has a plurality of branches.

FIG. 7 represents in top view a further modification of a piston flankaccording to the invention which differs from the other modificationsprimarily in that it is provided with turbulence chambers.

The circular piston internal combustion machine according to the presentinvention is characterized primarily in that the fuel chamberdepressions are provided with deflecting surfaces extendingsubstantially perpendicularly with regard to the direction of rotationof the piston, for deflecting the fuel gas. Such an arrangement bringsabout that above all the additional fuel gas flow which is brought aboutin addition to the fuel gas flow inherent to the rotation of the pistonin view of the varying spacing between the piston flank and the housingcontour, will be made use of for preparing the mixture. This is due tothe fact that the course of the flow and of the speed are determinedprimarily by the shape of the fuel chamber depression. At the respectiveplace of minimum distance between housing contour and piston flank, aspeed maximum occurs which means an additional flow. With regard to thepiston flank, this speed maximum moves counter to the direction of flowfrom one piston corner to the other. This additional flow will, when thefuel chamber trough is designed in a flow favoring manner, for instancewhen the cross-sectional shape of the fuel chamber depression remainsuniform over its entire length, not improve the turbulence of themixture. However, such improvement has been obtained by the deflectingsurfaces according to the present invention by means of which the fuelgas flow is deflected in a shock-like manner and is subjected toturbulence. This effect will be further improved and increased if eachfuel chamber depression is provided with a plurality of seriallyarranged deflecting surfaces and/or with deflecting surfaces arrangedadjacent to each other. Expediently, the deflecting surfaces are formedby the faces of deflecting bodies in the central portion of the fuelchamber depressions, and the fuel chamber depressions arecorrespondingly widened within the region of the deflecting bodies.

In conformity with a further development of the invention, the surfaceof the deflecting body in the direction of rotation of the piston is sodesigned that it drops toward the bottom of thefuel chamber depressionso that a deflection of the fuel gas. flow will also be obtained inradial direction.

The course ofthe flow and of the speed are particularly favorablyinfluenced by so designing the fuel chamber depression that they areangled off a plurality of times along their length and/or provided withbranches preferably at the start and at the end of the said fuel chamberdepression. This angling off may consist of two parallel spaced brancheswhich merge in a central portion of a somewhat greater width than thebranches, the deflecting surfaces being formed by the wall portionswhich at the merging areas are at least approximately perpendicular tothe direction of rotation of the piston.

According to a further development of the invention, turbulence chambersare arranged -atthe deflecting points for the fuel, which turbulencechambers are not directly passed through by fuel. The thus effectedreduction in the flow velocity with simultaneous strong turbulence andre-circulation will assure a satisfactory preparation of the fuel airmixture and will create favorable igniting conditions. It is for thisreason that the turbulence chambers should be associated with theignition source in such a way that the turbulence chambers will duringthe ignition be located in the region of the source of ignition. Withair compressing machines, this effect can be taken advantage of in aparticularly effective manner is, at least during the starting, theinjection of a portion of the respective fuel quantity into theturbulence chamber is effected.

Referring now to the drawings in detail, a deflecting body 3 is insertedinto the fuel chamber depression 1, which fuel chamber depression islocated in the piston flank of the rotary piston which rotates in thedirection of the arrow A. The fuel gas flow impacts upon andperpendicularly to the face side 4 of the deflecting body 3, which fuelgas flow which with the piston position corresponding to the compressionmaximum will at the lobe portion 5 of the housing contour 6 reach itsmaximum speed. In this way the fuel gas flow is divided and deflected.The short arrows indicated in FIG. 7 illustrate the course of the flowof the fuel gas. Laterally and rearwardly of the deflecting body 3 whichpreferably tapers in the direction of movement of the piston, and due tothe course of the longitudinal walls 7, a quieting down of the fuel gasflow and a distribution in width of said fuel gas flow will occur.

The fuel chamber depression according to FIG. 3 is provided with twoserially arranged deflecting bodies 3. In this way there will beobtained an increase in the region of the piston position over which thecreation of a turbulence of the fuel gas flow will be favored.

The deflecting body 3 according to FIGS. 4 and 5 flares in the directionof rotation of the piston and additionally is provided with an inclinedsurface 8. It will be appreciated that with this design, in addition toa lateral deflection of the fuel gas flow at the face side 4, also atthe depression transverse wall 9, a turbulence will be produced inradial direction.

The front and rear portion of the fuel chamber depression illustrated inFIG. 6 is formed by two parallel branches l0 and 11. The central portionconsists of a single trunk 12. In view of the angled-off portions at themerging areas, the respectively rearwardly facing walls (whenconsidering the direction of rotation of the piston) form the deflectingsurfaces 13 and 14 for the fuel gas flow.

With the fuel chamber depression shown in FIG. 7, only the rear portion(when looking in the direction of rotation of the piston) of the fuelchamber depression is provided with parallel branches 10. At the mergingareas with the trunk 12, bulged portions 15 are provided which formturbulence chambers. The deflection, retardation and turbulence of thefuel gas flow will be further increased by the turbulence chambers 15.

As will be evident from the above, the deflecting walls according to thepresent invention, individually or in combination with each other, bringabout the further advantage that the correspondingly equipped rotarypiston internal combustion machines can be operated over an extendedfuel air mixture range while at the same time the proportion of thenon-burned parts in the exhaust gases will be reduced and also the knocksensitivity will be reduced. Moreover, with air compressing machines, alarger portion of the air load will be made use of in connection withthe combustion which means that the fuel economy will be increased.

It is, of course, to be understood that the present invention is, by nomeans, limited to the particular showing in the drawings, but alsocomprises modifications within the scope of the appended claims.

While the piston of FIG. 2 is intended to be a triangular piston similarto the one disclosed in U.S. Pat. No. 3,319,610, also other polygonalpistons may be used in connection with the present invention.

What I claim is:

l. A circular piston internal conbustion machine which includes ahousing with a epitrochoidal inner contour, a shaft journalled in saidhousing and provided with an eccentric, a rotary piston rotatablerelative to said inner contour of said housing and journalled on saideccentric for rotation relative thereto, said piston being of polygonalcross-sectional shape so as to have a plurality of circumferentiallyspaced edge means extending in the direction of the axis of rotation ofsaid piston relative to said housing, said piston having those areasthereof which are located between said edge means and face said innercontour respectively provided with trough-shaped depressions formingcombustion chamber means and extending in the circumferential directionof said piston, each of said combustion chamber means located betweentwo circumferentially successive edge means including wall means havingdeflecting surface means extending substantially transverse to thedirection of rotation of said piston relative to said housing fordeflecting fuel gas in said chamber means in a direction transverse tothe circumferential direction of said rotary piston, and at least onedeflecting body arranged within said chamber means in the centralportion thereof and forming said wall means with said deflecting surfacemeans.

2. A machine according to claim 1, said chamber means widening withinthe region of said deflecting bodies with regard to those portions ofsaid chamber means which are located in front and behind said deflectingbodies when looking in the circumferential direction of said piston.

3. A machine according to claim 2, in which the top surface of saiddeflecting bodies is declining in the direction of movement of saidrotary piston relative to said housing.

4. A machine according to claim 3, in which the said top surface of saiddeflecting bodies drops at an incline down to the bottom of said chambermeans.

5. A machine according to claim 2, in which each of said chamber meansis provided centrally with at least one added impinging, disturbing, anddeflecting surface means, each chamber means has a plurality ofauxiliary deflecting means spaced from each other in the circumferentialdirection of said piston and forming said added deflecting surface meansrelative to depressions.

6. A machine according to claim 5, in which each of said chamber meansis provided centrally with at least one added impinging, disturbing, anddeflecting surface means, each of said chamber means is provided with aplurality of added deflecting surfaces laterally of the plane ofsymmetry extending through said chamber means in the circumferentialdirection of said piston relative to depressions.

7. A machine according to claim 1, in which said deflecting wall meansinclude turbulence chamber means.

8. A machine according to claim 7, which includes ignition meansdistributed relative to the circumference of said piston, and in whichthe speed of rotation of said piston relative to said housing is suchthat said ignition means will be in the region of said turbulencechamber means when ignition of fuel therein is desired.

9. A machine according to claim 2, in which said deflecting bodies areof a predetermined shape when viewed from the top, and have one endportion pointing in the direction of rotation of the piston relative tosaid housing.

10. A machine according to claim 2, in which said deflecting bodies havethe shape of a trapezoid when viewed from the top with the base of thetrapezoid facing in the direction of rotation of said piston relative tosaid housing.

11. A machine according to claim 9, in which the chamber means togetherwith opposite sides of said deflecting bodies form oppositely locatedpassage means increasing in cross-section from the basis of therespective deflective body to the end portion thereof and leading to aportion of said chamber means between two successive deflecting bodies.

1. A circular piston internal conbustion machine which includes ahousing with a epitrochoidal inner contour, a shaft journalled in saidhousing and provided with an eccentric, a rotary piston rotatablerelative to said inner cOntour of said housing and journalled on saideccentric for rotation relative thereto, said piston being of polygonalcross-sectional shape so as to have a plurality of circumferentiallyspaced edge means extending in the direction of the axis of rotation ofsaid piston relative to said housing, said piston having those areasthereof which are located between said edge means and face said innercontour respectively provided with trough-shaped depressions formingcombustion chamber means and extending in the circumferential directionof said piston, each of said combustion chamber means located betweentwo circumferentially successive edge means including wall means havingdeflecting surface means extending substantially transverse to thedirection of rotation of said piston relative to said housing fordeflecting fuel gas in said chamber means in a direction transverse tothe circumferential direction of said rotary piston, and at least onedeflecting body arranged within said chamber means in the centralportion thereof and forming said wall means with said deflecting surfacemeans.
 2. A machine according to claim 1, said chamber means wideningwithin the region of said deflecting bodies with regard to thoseportions of said chamber means which are located in front and behindsaid deflecting bodies when looking in the circumferential direction ofsaid piston.
 3. A machine according to claim 2, in which the top surfaceof said deflecting bodies is declining in the direction of movement ofsaid rotary piston relative to said housing.
 4. A machine according toclaim 3, in which the said top surface of said deflecting bodies dropsat an incline down to the bottom of said chamber means.
 5. A machineaccording to claim 2, in which each of said chamber means is providedcentrally with at least one added impinging, disturbing, and deflectingsurface means, each chamber means has a plurality of auxiliarydeflecting means spaced from each other in the circumferential directionof said piston and forming said added deflecting surface means relativeto depressions.
 6. A machine according to claim 5, in which each of saidchamber means is provided centrally with at least one added impinging,disturbing, and deflecting surface means, each of said chamber means isprovided with a plurality of added deflecting surfaces laterally of theplane of symmetry extending through said chamber means in thecircumferential direction of said piston relative to depressions.
 7. Amachine according to claim 1, in which said deflecting wall meansinclude turbulence chamber means.
 8. A machine according to claim 7,which includes ignition means distributed relative to the circumferenceof said piston, and in which the speed of rotation of said pistonrelative to said housing is such that said ignition means will be in theregion of said turbulence chamber means when ignition of fuel therein isdesired.
 9. A machine according to claim 2, in which said deflectingbodies are of a predetermined shape when viewed from the top, and haveone end portion pointing in the direction of rotation of the pistonrelative to said housing.
 10. A machine according to claim 2, in whichsaid deflecting bodies have the shape of a trapezoid when viewed fromthe top with the base of the trapezoid facing in the direction ofrotation of said piston relative to said housing.
 11. A machineaccording to claim 9, in which the chamber means together with oppositesides of said deflecting bodies form oppositely located passage meansincreasing in cross-section from the basis of the respective deflectivebody to the end portion thereof and leading to a portion of said chambermeans between two successive deflecting bodies.